Homo means same. hetero means opposite
The theory of Continental Dift
I believe the answer is incomplete dominance. Incomplete dominance creates a mix of the two phenotype(white and dark purple flowers) to create a third phenotype (lavender). Lavender is a mix.
Whereas, co-dominance would not be a mix but both traits would exist within the organism. In your question, it would be codominance if the dark purple flower and the white flower created a flower with white and dark flower pedals. This would not be a mix of the phenotype, but a co-existance of both phenotype.
I hope that helps! :D
A variation is a reference to the differences or deviations, such as the structure and form, as for crossing over is the exchange of genetic material between the non-sister chromatids of the homologous chromosomes during meiosis.